So we did it a couple of times and they said, ‘OK, that’s great, let’s just improvise it now,’ and you know I just sort of looked at Lizzy and she looks at me and I thought, ‘I’m a robot, and you’re a witch, how are we gonna do this?’
Well it was about 100 degrees and we were really, really sweaty, and the Russo brothers ran over to us and went, ‘So the entire beating heart of the movie is now on your shoulders.
We went off and just wrote some stuff together and then we came back in.